describe('failing test', () => {
  const Fixture = () =>
    <div>
      <span style={{ background: 'black' }} />
    </div>;

  it('fails toHaveStyle', () => {
    expect(shallow(<Fixture />).find('span')).toHaveStyle('fontSize');

    expect(shallow(<Fixture />).find('span')).toHaveStyle('fontSize', 5);
  });

  it('fails NOT toHaveStyle', () => {
    expect(shallow(<Fixture />).find('span')).not.toHaveStyle(
      'background',
      'blue'
    );
  });
});
